With improvement of people's living standard, electronic products (such as flashlight, electric fan, electric shaver, desk lamp, headlight, camping light) have become necessary supplies. These electronic products are needed to charge up frequently due to the frequent use and the limitation of using places. Conventional charging includes two ways, one way is connecting the electronic product with the charging plug via a data line, and therefore electricity can be conducted into the battery so as to store the electricity into the battery; the other way is disassembling the battery from the electronic product and assembling it to the charger to charge. One on hand, since the first way must use data line to accomplish the charging, one end of the data line must be inserted into the electronic product while charging and then pulled out after charging, which is quite inconvenient and problems such as disconnection or socket looseness etc. will be generated. Thus the charging effect is unstable and furthermore it will damage the electronic products. On the other hand, regarding to the emergency lamp and camping light etc., as these electronic products are often in the state of charge when they are unused, and when they are needed to use, it's hard for user to take the product from the charge base in time. Therefore, non-contact charging equipments have been developed.
Referring to US Pub. No. 2010/0066251, which discloses a charging equipment used in the emergency lamp. The charging equipment includes a charger base, a sensing transmitting module mounted in the charger base and a sensing receiving module mounted in a housing of the emergency lamp. Therein, a large sensing coil in the output terminal of the sensing transmitting module encircles a small sensing coil in the input terminal of the sensing receiving module. When operates, electricity inputted from the plug is translated into magnetic energy by the large sensing coil and then the magnetic energy is translated into sensing voltage by the small sensing coil so as to charge up the rechargeable battery of the emergency lamp. However, as the sensing parts of the above-mentioned charging equipment are formed by a small sensing coil and a large sensing coil encircled the small sensing coil, thus the total sensing coils are too large, the copper wires needed to use are increased, therefore the weight is increased which causes a high cost. Moreover, as the size of the sensing parts is overlarge, thus it's not applicable to small products.
Thus, there is a need for a sensing charger to overcome the above-mentioned drawbacks.